The Toyota website shows the 08 Highlander hybrid model as having an EV mode button as standard equipment. I hope the 08 Prius has that also. Rob
Even better than a factory EV button is the friggin' optimization meter. It's a gauge that shows you if you're in the sweet-zone for maximum mpgs as far as throttle is concerned. I went to the Ride and Drive for the 08 highlander, and I have to say it's freaking sweet. The new hybrid, though, is basically the same thing in a different shell. They added an EV button, an Econ button (throttle control), and that optimization gauge. I hope they put all three on the next prius and camry hybrid. ps...I'm a toyota salesperson if you couldn't figure that out.
Not for 08... maybe when the next gen Prius comes around (and it probably has to if there's a plug-in option)